Stair structure



N. BOIS.

STAIR STRUCTURE. APriLlcATloN man )mL-12. |920.-

PatentedSept. 21

2 SHEETS-SHEET 1.

dii-tomi 243 0 N. BOIS.

STAIR STRUCTURE.

.APPLICATION 4man APR. l2. |920.

'Ptented Sept. 21,1920.

2 SHEETS-SHEET 2.

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Unirse srarss rarest ort-"ica NATHANIEL BOIS, 0F SAN FRANCISCO,CALIFORNIA.

ST1-HR STRUCTURE.

Patented Sept. 21, 1920.

` Application filed April 12, 1920. Serial No. 373,214.

T o all 'whom it may concern.

Be it known that 1, NATHANIL Bois, a citizen of the United States,residing at San Francisco, in the county of San Francisco and 'State ofCalifornia, have invented certain new and useful Improvements in StairStructure; and l do declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertainsto make and use the same.

character,

This'invention relates to stair structure, and more specifically to acombination of improved metal stair structure. t

The main object of this invention is to generally improve upon devicesof this and especially to improve upon my prior Patents Nos. 724790,750156, 1244021 and 1304533, by providing animproved combination whichis exceedingly simple in construction, embodying oomparatively few andeasily formed parts, these parts being exceedingly easily assembled;also combining the improved interlocking features and securing meansshown (uncombined) in the several prior patents designated in theforegoing.

Other objects and advantages will be pointed out or implied in thefollowing details of description in connection with the accompanyingdrawings, in which:

Figure 1 is a longitudinal vertical seotional view through `a portion ofstair structure made in accordance with the present invention, thesection being taken substantially along the line 1-1 of Fig. 2.

Fig. 2 is a vertical sectional view, the section being takensubstantially alongtgthe line 2-2 of Fig. 1.

Fig. 3 is a perspective view of one sheet metal step member.

Fig. 4 is a view similar to Fig. 1, but illustrating a somewhat modifiedform ofthe invention.

Fig. 5 is a view somewhat similar to Fig. 2, but illustrating themodified form shown in Fig. 4, the section being taken along the line5-5 of Fig. 4. f

Fig. 6 illustrates a modified form used where the soflit is to beplastered.

Fig. 7 is a sectional view along the line 7--7 of Fig. 6. y

Fig. 8 illustrates a modified form of combined tread seat and riser. p

Referring to these drawings'in detail, in

which similar parts views are designated by similar referencecharacters, the inventi consists in.. the combination and arrangementofparts. as will' now be specifically described and claimed.

In certain'forms of this present invention, illustrated at 6 in my prior-Patent, No.` 7 50156, these stringers being formed with an inwardlyprojecting-flange 2 and an'outwardly projecting flange 3, the latterbeing integral with the upper while the former is integral with thelower of its stringer, the lower flange being provided with a series ofapertures through which securing bolts 4 extend. A

The sheet metal step membershown in Fig. 3 combines certain importantfeatures illustrated in my prior Patents Nos. 1244021 and 1304533, thatis, it combines vthe interlocking elements 7 and 8v of the former ofthese.

patents with 10 jformed with an upportion 9. AIt will that the lowersurface of each portion 9 is parallel with the flange 2 of each bar orStringer 1, so that a very close and solid connection is obtainedbetween these step members .and the flanges 2.

Itis to be understood that'the ends of the step members fit snuglyagainst the vertical. inner surfaces -of the stringers 1, so that. asubstantially non-leakable receiver is formed by the union of they stairmembers and stringers, and in order to insure such close fitting and torender these receptacles non-leakable, and also to obtain the greateststrengthand rigidity consistent with few and simple parts, long bolts ortie rods 12 are employed in a manner somewhat. similar to thatillustrated in my 1 and 4, it will be seen 4, is provided with at nutwhich is seated .on the upper surfaceof `the upwardly inclined valso beseen prior' Patent No.

throughout 4the several .the stringers 1 are substantially of the formedge of its Stringer,

Fig. 3) has a tread-supv inwardly extending flange 8 at l thebolts 4.4By

724790. However, the bolts are formed,in this invention, with round orconvex heads 12". The bolts `12 extend, from the outerv Stringer-1 toand through the inner Stringer 1, these stringers being apertured at 13'for receiving the bolts 12, and the inner end of each bolt 12 isprovided with a nut 12b which is seated against the surface on which theangle-iron or beam 5 is secured. The space between the upper flan e 3and the bar 5 provides ample room or the inner ends ofthe bolts 12 sothat the latter do l not interfere'with the wall w and cannot beinterfered with by the Wall or any person after the stair structure hasbeen secured in place against the wall.

As in `my prior patent, treads 14 may be formed by filling thereceptacle with con crete or other pla'stic material, and thesetreads`l4 not only cover and hide the nuts and-the inner ends of thebolts 4, but also 'prevent these nuts from being turned, and

tend to prevent the bolts frombeing turned,

since the upper' ends of the latter extend beyond thenuts and areembedded in the concrete or plastic material. The outwardly projectingflange 8 of the "inner Stringer 1 provides a plaster-strip or means todefine the limit of the lower edge of the plaster above the stairwa andit is yclearly within the scope of this invention to provide this upperportion of' the inner Stringer with a longitudinal groove or' channelsuch as shown at 6. Moreover, 'it

is within the scope of this invention to form the angle-bar 5 integrallywith theinner Stringer 1, instead of making it primarily .separate andattaching it in the manner' illustrated. However, the form illustratedappropriatel means;

is preferable where the stringers are formed from strips of sheet metaland have their' edges turned by means ofa brake or other meansillustrated at 7a he interlocking? ig. 4, may be employed andk 8a, shownin in lieu'of that illustrated at 7 and 8 in Fig.'-

1, and other changes may be made within l the scope of the claims.

`Inthe modified form shown in Figs. 6

mnd 7 thel angle-iron 5 is eliminated from the inner Stringer 1, and the.outer Stringer -1a has an yangle-iron 1b secured thereto or thisangle-iron having an inwardly extendunitedthei'ewith by any appropriatemeans,

ing flange on which the tread supporting element 10 rests,

The plaster sollit is indicated at Pnthuei' "j same being applied tometal lathwoi`- ex.-y

panded metal, as indicated at lo, this metal la'lth being secured inplace by the bolts 4 or by any appropriate means. "What I claimas myinvention is :f 4 1.- In a stair structure, a pair of 'stringere eachprovided with an inwardly extending l apertured flange` adjacent toitslower edge, Va vpluralityoii stair stepseach formedof single-piece ofsheet metal and comprising a horizontal treadecarrying portion and' -avertical riser portion, the front edges of the upper tread-carryingportions beinginterlocked with the upper edges of the riser iportions,the junctions of the tread anda-riser portions being seated on saidinwardly extending fianges and provided with apertures i that registerwith thoseof vsaid flanges, bolts extending through these registeringaperi 'lasl tures and provided with nuts, treads secured on saidtread-supporting portions, and bolts each extending through bothof saidstringers'.

and substantially throughout the Width of -the stairstructure, eacholi-these latter bolts bein disposed directly under the respective trea-carrying portions rearward of theyre` spective interlocking portions ofthet'readcarrying tportions and risers.-

2. In .'a'stair structure,`a pair of sheet metal stringers each providedwith antinwardly extending apertured flange adjacent to its lower edge,a plurality of stair steps each formed of a single piece of sheetmeta'lland comprising a horizontal treadfcarrymg portion and la vertical riserportion, thev iront edges of the upper tread-carrying or#y tionsv beinginterlocked with the upper er of the lower riser portions, thejunctionsof the tread and -riser portions being parallel" with andseated` on said inwardly extending flanges and provided with aperturesthat register with those of said flanges, bolts extending up throughthese registering aperturcs and provided with nuts .on their upperyends, treads secured on said tread-supporting portions by theinterlockin 'parts of the treads and.v risers, these treaA s concealingand guardingsaid nuts, and bolts eachfexy

